Counter

Description

Unlike many of the other examples, this one is not really a problem to be solved. Rather, the Counter example uses multiple instances of the simple class COUNTER to explore various concurrent scenarios. Each instance of COUNTER has a unique identifier, a current value, and a speed. A counter's speed is that time that it takes to perform a single increment. You will see that some of the tests start multiple counters at different speeds. Class COUNTER has a procedure run which takes an integer as an argument, and increments the counter that many times. The example's root class contains the code to create counter instances and run the various tests.

Highlights

There are six tests that can be called from the root procedure:

make -- Test counters. do print ("Counter application%N") -- Leave one of the following lines uncommented to perform testing. test_1 -- start just one counter -- test_2 -- start two counters -- test_3 -- start many counters -- test_4 -- start counter_1 twice -- test_5 -- start counter_1 with precondition -- test_6 -- start counter_1 separately and counter_2 non-separately end

You can uncomment the test that you want to run and leave the rest commented. When you run the test, you can see you can watch the output in the console window as the test progresses.

Have a look at the source code for each test before you run it, so that you can reconcile the output you see with your expectation of the execution.